Its melting point lies between 61° and 78°, although occasionally higher. In
general a product with m.pt. above 66° is regarded as pure ceresine. Such
limits are, however, not valid if the ceresine contains carnauba wax.
Montan wax is obtained by the treatment of the lignites of Saxony. In
its appearance it resembles ozokerite or mineral wax, but in composition it
is completely different.
Crude montan wax is black or dark brown, but the purified product is
white or yellowish and of fibrous-crystalline appearance.
The determinations made are usually as follows:
1. Melting Point.—As for paraffin wax (q.v., 2).
2. Acidity.—The product is dissolved at a gentle heat in a mixture
of ethyl and amyl alcohols (i : 2) and the solution titrated with decinormal
potassium hydroxide solution in presence of phenolphthalein (Holde's
3. Saponification Number.—About 2 grams of the wax are boiled
for six hours in a reflux apparatus with 40 c.c. of benzene and 25 c.c. of
seminormal potassium hydroxide, the excess of the latter being subsequently
titrated with a seminormal acid.
4. Unsaponifiable Substances.—2 grams of the wax are saponified
as above, the solution evaporated to dryness on a water-bath with 30 grams
of granular sand, and the residue extracted in a Soxhlet apparatus with
Crude montan wax has m.pt. 80-84°, acid number 18-28, Saponification
number 80-90 ; the purified product has m.pt. 83-84°, acid number 93-100,
and Saponification number 94-106.
Besides heavy mineral oils and vegetable and animal oils and fats (see
corresponding chapters), use is made as lubricants of mixtures of mineral
oils with fatty oils (see Heavy Mineral Oils) and of complex mixtures which
may contain fats, resins, alkaline and alkaline-earthy soaps, mineral oils,
resin and tar oils, in addition to water and mineral matter (lime, talc,
Of these complex lubricants the principal ones are the stiff lubricants,
which include cart-grease and usually contain mineral or resin oils with
lime soaps and mineral substances, and the emulsive lubricants, formed of
pale mineral oils with alkaline or ammonium soaps or sulphoricinates.
1. Stiff Lubricants
These are solid or semi-solid products of varying appearance. In
addition to noting the colour, consistency, homogeneity and odour, the
following tests are usually made : p. 109.g between 60° and 66° as a mixture